Next term what he wants to do is -----in another school.是填to

Next term what he wants to do is _____in another school.是填to teach 还是 teachNext term what he wants to do is _____in another school.好象有一个规律是：主句有do,省略作表语的不定式的to.但是我在同一本语法书上又看到一个例句,不是填空,是例句.就是上面这句话,中间是to teach,我觉得矛盾了.